1. Field of the Invention
The present invention relates to a constant velocity universal joint for connecting a first shaft as one transmission shaft and a second shaft as the other transmission shaft, for example, in a driving force-transmitting section of an automobile.
2. Description of the Related Art
Constant velocity universal joints are commonly used in motor vehicle applications. The constant velocity universal joint is disposed in a driving force-transmitting section of an automobile for connecting a first shaft as one transmission shaft and a second shaft as the other transmission shaft so that a rotary force is transmitted to respective axles.
The present applicant has proposed a constant velocity universal joint and an assembling method thereof in U.S. Pat. Nos. 6,454,655 and 6,497,621. According to the constant velocity universal joint, induced thrust performance and durability are improved by reducing slide resistance generated when one transmission shaft is tilted and a trunnion is displaced along a guide track. The present invention has been made in relation to this proposal.
A general object of the present invention is to provide a constant velocity universal joint by implementing the assembling method according to the above proposal. According to the present invention, without decreasing the assembling performance, the diameter of a neck of a trunnion is increased so that strength of the trunnion is increased.
A principal object of the present invention is to provide a constant velocity universal joint by implementing the assembling method according to the above proposal. According to the present invention, without decreasing the assembling performance, the diameter of a neck of a trunnion is increased so that productivity in forging the trunnion is improved.
The above and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which a preferred embodiment of the present invention is shown by way of illustrative example.